Active Power Dispatch Plan among Units in DFIG Based Wind Farm

During normal operation, doubly-fed induction generator (DFIG) can generate certain range of reactive power according to the requirements of the power grid. According to the active power order from power dispatching center, a kind of wind turbines scheduling solution which also suits the actual operation situation of “three-north” area wind farms in China is proposed. This solution makes it possible for the wind farm to generate the maximum reactive power or the certain reactive power below the maximum reactive power which will meet the needs of the power grid by adjusting output active power and reactive power of each DFIG. Based on the DFIG reactive power limit, this paper proposes two theorems and an allocation algorithm to find out the active power dispatch plan. This plan avoids the grid side converter switch devices frequently action. The active power and reactive power generated by the wind farm can both satisfy the power grid’s needs and provide a reference for the capacity of additional reactive power compensation device. The effectiveness of the active power and reactive power dispatch plan is verified in case study.